Xin Ye, Wei-Ming Kang, Jian-Chun Yu, Zhi-Qiang Ma, Zhi-Gang Xue, Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing 100730, China
Author contributions: Ye X and Kang WM contributed equally to this work; Ye X, Kang WM and Yu JC designed the research; Ye X, Kang WM and Yu JC performed the research; Ma ZQ and Xue ZG analyzed the data; Ye X, Kang WM and Xue ZG wrote the paper.
Institutional review board statement: The study was reviewed and approved by the Ethics Committee of Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College.
Informed consent statement: All study participants, or their legal guardian, provided informed written consent prior to study enrollment.
Conflict-of-interest statement: The authors have no conflicts of interest to declare.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Jian-Chun Yu, MD, Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, No. 1 Shuai Fu Yuan, Dongcheng District, Beijing 100730, China. email@example.com
Telephone: +86-10-69152213 Fax: +86-10-69152213
Received: March 23, 2017
Peer-review started: March 26, 2017
First decision: April 7, 2017
Revised: April 10, 2017
Accepted: June 1, 2017
Article in press: June 1, 2017
Published online: July 7, 2017